原Po第一題有點不完整
每一個麥農有U形的平均總成本曲線
並達到LAC(min)=3，每位產出10單位
原本需求線是Q=3600-200p
Q*=3600-200(3)=3000
廠商家數=3000/10=300
然後，接著你的問題
P=MC=0.3q q=P/0.3
Q=300(p/0.3)=1000P
(新的需求線）
7200-200p=1000p P*=6 Q*=6000
P*=MC=0.3q q*=20
MC=0.3q 積分 TVC=0.15q^2
TC=0.15q^2+TFC
LAC=0.15q+TFC/q
對LAC微分得0 （MES)
0.15-TFC/q^2=0 q=10代入（MES)
得到TFC=15
兀=60*20-0.15(20^2)-15=45
※ 引述《claudina (claudina)》之銘言：
: Suppose demand shifts to Q(P)=7200-200P. If the number of farmers is fixed
: in the short run and each produces with a marginal cost given by MC(q)=0.3q,
: where q denotes the number of bushels produced. What is the profit a typical
: farmer makes?
: In the 1970s, people had become accustomed to high inflation in the United
: States. In 1979, the Fed decided to fight inflation and decreased the money
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: recession. Is thos thinking consistent with the aggregate demand and aggregate
: supply model? Explain.
: 假設某國的石油產業裡只存在兩家廠商, 其產品品質與生產技術完全一樣. 並且,
: 兩家廠商的固定成本為零, 每單位邊際成本為14元. 若市場需求函數為P=50-0.001X,
: 其中X代表第1家廠商產量X1與第2家廠商產量X2的總和, 亦即X=X1+X2;並且,
: 這兩家廠商均相信對方廠商的產量決策不會因為自己產量變動而有所改變. 請問:
: 當兩家廠商勾結成聯合獨賣, 則均衡下的兩家廠商產量與利潤各為何?
: 請大家幫幫我!